[MTD NAND] Update CS553x NAND driver: Hardware ECC support, optimisations.

- Implement HW ECC support,
- Provide read_buf() and write_buf() routines using memcpy
- Use on-flash bad block table
- Fix module refcounting
- Avoid read/modify/write in hwcontrol()
- Minor cosmetic fixes

Partly based on code and ideas from Tom Sylla <tom.sylla@amd.com>

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
This commit is contained in:
David Woodhouse 2006-05-13 04:12:40 +01:00
parent c3f8abf481
commit 9d75414b4f

View file

@ -4,6 +4,7 @@
* (C) 2005, 2006 Red Hat Inc.
*
* Author: David Woodhouse <dwmw2@infradead.org>
* Tom Sylla <tom.sylla@amd.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
@ -22,6 +23,7 @@
#include <linux/pci.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/nand_ecc.h>
#include <linux/mtd/partitions.h>
#include <asm/msr.h>
@ -87,11 +89,34 @@
#define CS_NAND_ECC_CLRECC (1<<1)
#define CS_NAND_ECC_ENECC (1<<0)
static void cs553x_read_buf(struct mtd_info *mtd, u_char *buf, int len)
{
struct nand_chip *this = mtd->priv;
while (unlikely(len > 0x800)) {
memcpy_fromio(buf, this->IO_ADDR_R, 0x800);
buf += 0x800;
len -= 0x800;
}
memcpy_fromio(buf, this->IO_ADDR_R, len);
}
static void cs553x_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
{
struct nand_chip *this = mtd->priv;
while (unlikely(len > 0x800)) {
memcpy_toio(this->IO_ADDR_R, buf, 0x800);
buf += 0x800;
len -= 0x800;
}
memcpy_toio(this->IO_ADDR_R, buf, len);
}
static unsigned char cs553x_read_byte(struct mtd_info *mtd)
{
struct nand_chip *this = mtd->priv;
unsigned char foo = readb(this->IO_ADDR_R);
return foo;
return readb(this->IO_ADDR_R);
}
static void cs553x_write_byte(struct mtd_info *mtd, u_char byte)
@ -110,35 +135,29 @@ static void cs553x_hwcontrol(struct mtd_info *mtd, int cmd)
{
struct nand_chip *this = mtd->priv;
void __iomem *mmio_base = this->IO_ADDR_R;
uint8_t old = readb(mmio_base + MM_NAND_CTL);
unsigned char ctl;
switch(cmd) {
case NAND_CTL_SETCLE:
old |= CS_NAND_CTL_CLE;
ctl = CS_NAND_CTL_CLE;
break;
case NAND_CTL_CLRCLE:
old &= ~CS_NAND_CTL_CLE;
case NAND_CTL_CLRALE:
case NAND_CTL_SETNCE:
ctl = 0;
break;
case NAND_CTL_SETALE:
old |= CS_NAND_CTL_ALE;
break;
case NAND_CTL_CLRALE:
old &= ~CS_NAND_CTL_ALE;
break;
case NAND_CTL_SETNCE:
old &= ~CS_NAND_CTL_CE;
ctl = CS_NAND_CTL_ALE;
break;
default:
case NAND_CTL_CLRNCE:
old |= CS_NAND_CTL_CE;
ctl = CS_NAND_CTL_CE;
break;
}
writeb(old, mmio_base + MM_NAND_CTL);
writeb(ctl, mmio_base + MM_NAND_CTL);
}
@ -151,6 +170,29 @@ static int cs553x_device_ready(struct mtd_info *mtd)
return (foo & CS_NAND_STS_FLASH_RDY) && !(foo & CS_NAND_CTLR_BUSY);
}
static void cs_enable_hwecc(struct mtd_info *mtd, int mode)
{
struct nand_chip *this = mtd->priv;
void __iomem *mmio_base = this->IO_ADDR_R;
writeb(0x07, mmio_base + MM_NAND_ECC_CTL);
}
static int cs_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code)
{
uint32_t ecc;
struct nand_chip *this = mtd->priv;
void __iomem *mmio_base = this->IO_ADDR_R;
ecc = readl(mmio_base + MM_NAND_STS);
ecc_code[1] = ecc >> 8;
ecc_code[0] = ecc >> 16;
ecc_code[2] = ecc >> 24;
return 0;
}
static struct mtd_info *cs553x_mtd[4];
static int __init cs553x_init_one(int cs, int mmio, unsigned long adr)
@ -167,7 +209,7 @@ static int __init cs553x_init_one(int cs, int mmio, unsigned long adr)
}
/* Allocate memory for MTD device structure and private data */
new_mtd = kmalloc (sizeof(struct mtd_info) + sizeof (struct nand_chip), GFP_KERNEL);
new_mtd = kmalloc(sizeof(struct mtd_info) + sizeof (struct nand_chip), GFP_KERNEL);
if (!new_mtd) {
printk(KERN_WARNING "Unable to allocate CS553X NAND MTD device structure.\n");
err = -ENOMEM;
@ -178,8 +220,8 @@ static int __init cs553x_init_one(int cs, int mmio, unsigned long adr)
this = (struct nand_chip *) (&new_mtd[1]);
/* Initialize structures */
memset((char *) new_mtd, 0, sizeof(struct mtd_info));
memset((char *) this, 0, sizeof(struct nand_chip));
memset(new_mtd, 0, sizeof(struct mtd_info));
memset(this, 0, sizeof(struct nand_chip));
/* Link the private data with the MTD structure */
new_mtd->priv = this;
@ -196,27 +238,33 @@ static int __init cs553x_init_one(int cs, int mmio, unsigned long adr)
this->dev_ready = cs553x_device_ready;
this->read_byte = cs553x_read_byte;
this->write_byte = cs553x_write_byte;
this->read_buf = cs553x_read_buf;
this->write_buf = cs553x_write_buf;
/* 20 us command delay time */
this->chip_delay = 20;
this->eccmode = NAND_ECC_SOFT;
this->chip_delay = 0;
this->eccmode = NAND_ECC_HW3_256;
this->enable_hwecc = cs_enable_hwecc;
this->calculate_ecc = cs_calculate_ecc;
this->correct_data = nand_correct_data;
/* Enable the following for a flash based bad block table */
// this->options = NAND_USE_FLASH_BBT;
this->options = NAND_USE_FLASH_BBT | NAND_NO_AUTOINCR;
/* Scan to find existance of the device */
if (nand_scan (new_mtd, 1)) {
if (nand_scan(new_mtd, 1)) {
err = -ENXIO;
goto out_ior;
}
new_mtd->owner = THIS_MODULE;
cs553x_mtd[cs] = new_mtd;
goto out;
out_ior:
iounmap((void *)this->IO_ADDR_R);
out_mtd:
kfree (new_mtd);
kfree(new_mtd);
out:
return err;
}
@ -283,7 +331,7 @@ static void __exit cs553x_cleanup (void)
iounmap(mmio_base);
/* Free the MTD device structure */
kfree (mtd);
kfree(mtd);
}
}
module_exit(cs553x_cleanup);